Physics Two Dimensional Motion Question 311

Question: What is the value of linear velocity, if $ \vec{\omega }=3\hat{i}-4\hat{j}+\hat{k} $ and $ \vec{r}=5\hat{i}-6\hat{j}+6\hat{k} $

[Pb. PMT 2000]

Options:

A)$ 6\hat{i}+2\hat{j}-3\hat{k} $ B)$ -18\hat{i}-13\hat{j}+2\hat{k} $ C) $ 4\hat{i}-13\hat{j}+6\hat{k} $ D)$ 6\hat{i}-2\hat{j}+8\hat{k} $

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Answer:

Correct Answer: B

Solution:

$ \overrightarrow{v}=\overrightarrow{\omega }\times \overrightarrow{r}=| \begin{matrix}{\hat{i}} & {\hat{j}} & {\hat{k}}\3 & -4 & 1\5 & -6 & 6\ \end{matrix} |=-18\hat{i}-13\hat{j}+2\hat{k} $